A noted deficiency in prior art culinary mixers is a tendency for so-called bridging, i.e. the effect that as food is added to a container of the mixer and as agitator blades of the mixer are rotated, there is a strong tendency for the product inside the container which is in close proximity to the rotating blades to become liquefied while preventing unprocessed material to be transported to the rotating blades to become disintegrated or blended. It is as if a bridge is formed between the rotating blades and the unprocessed product by a liquefied zone of disintegrated product.
Patent publication U.S. Pat. No. 4,256,407 discloses a mixer in an arrangement to overcome the bridging effect. The mixer of U.S. Pat. No. 4,256,407 is comprised of a container having two lobes. The container is fitted with a cover and in operative communication with a base having a motor. The container is fabricated by joining two partial cylinders along the arcs thereof. The lobes form semi-independent agitation zones, each provided with a rotatable blender blade therein. As the blades rotate, the semi-independent agitation zones are established within the lobes such that a material flow is established from top to bottom.
However, a bridging effect may still be initiated when difficult food products such as meats and products of high viscosity are processed.